Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization

First Edition

© 1975-1979, 2008 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Xenology: An Introduction to the Scientific Study of Extraterrestrial Life, Intelligence, and Civilization, First Edition, Xenology Research Institute, Sacramento, CA, 1979; http://www.xenology.info/Xeno.htm


12.2.1  Intersexuality

While we might expect maleness and femaleness to be well defined among most bisexual alien species, intersexuality constitutes a major exception to this rule. Intersexuality is a state in which an organism is neither strictly female nor strictly male. Rather, it displays some alternate, intermediate, or variable condition that lies somewhere in between.2494

There are two major classes of intersexes.

The first of these is illustrated by a strain of fruit fly (Drosophila) which has three copies of all its chromosomes instead of the normal two. In most bisexual hereditary systems, each parent contributes one set of genes -- including the sex-determining ones -- to the offspring. But with three sets, this special strain of fly can attain intermediate states of sexual expression. Using artificial breeding techniques, any desired degree of intersexuality may be arranged: 30% male/70% female, 60% male/40% female, and so forth.

These insects, and various higher animals such as the bovine freemartin (the female of a male-female twin pair in cattle), are called spatial intersexes. They are stuck with their ambiguous constitution for the rest of their lives. They cannot change, and are often sterile.

Hermaphrodites represent an interesting special case of spatial intersexuality. A "simultaneous hermaphrodite" is an organism which possesses at once both female and male sex organs. Ovaries and testes are present together in the same individual. Planarians, earthworms, annelids, sponges, hydras and snails exhibit this form of bisexuality.2493 A few vertebrate simultaneous hermaphrodites are known, such as the banded flamefish (Serranus subligarius).

But the intersexual animal can be a sex-mosaic in time as well as space. There are many organisms, of which the gypsy moth Lymantria is but one example, which start life as one sex and finish it as another. This condition, in which the two sexes are separated temporally, is called temporal intersexuality or "sequential hermaphroditism."

Sequential hermaphrodites come in many varieties. Protoandry is a system where an animal is first male, and later female; proterogyny is the converse, with young females metamorphosing into functional males as they age. And there are many other more complicated arrangements. Populations of sea anemones, for example, consist only of females and simultaneous hermaphrodites, a condition known as gynodioecy.

What would a temporal intersexual extraterrestrial be like? We can take a few clues from the freshwater shrimp Gammarus pulex. Each individual crustacean is both male and female, but not at the same time. Newborn animals spend early life in a neuter stage, after which they pass through puberty and enter the first sexually active phase as functioning males.

After a while, the maleness is exhausted. Latent ovaries ripen into maturity, and the organism spends the remainder of its life as a full-fledged female. Eggs are shed by middle-aged mothers and fertilized by energetic youthful males (who are still in the middle of their first cycle).

It is a magnificent bisexual system, one that works quite well on this planet. No one is excluded from any phase of the reproductive process. Still more significant, each member of the colony plays both male and female roles during his/her life. This cannot fail to have major effects on the intensity and depth of interpersonal relationships among these beings. In the case of such hermaphroditic aliens, the impact on the development of society, patterns of competition and aggression, laws and government, and attitudes toward the young are scarcely imaginable. (Science fiction writers have had a field day with this theme.97,226,442)

If there exist extraterrestrial hermaphrodites patterned after the freshwater shrimp on some other planet, what would their lives be like? Dr. Norman J. Berrill, Professor of Zoology at McGill University in Montreal, gives us some insight into the lifestyle of a temporal intersexual alien:

[Measured against a human yardstick], all half-grown individuals, about ten years old and weighing about 34 kilograms, would be males, the only males, ready to act as such both sexually and probably in other wayward ways. But as troublemakers like their truly human counterparts they would undoubtedly be kept in place by a closed society of matriarchs, roughly equal in number to the males, each twice the weight and much older and wiser. And not only wiser in a general way, but in the special sense of having each been a male herself, as understanding as a mother with a child and as little likely to put up with any nonsense, perhaps wistfully looking back to her youthful manhood. Girlhood would bud as usual when masculinity had faded, with growth continuing and full female maturity yet to come. Apart from lovelife the only question is, who would do man’s work? Little men browbeaten by large women who once had been little men themselves, or the women themselves, whether full-grown and breeding or not?89

Of course, the reverse of the above is also quite possible in ET races, although it appears much less common among the fauna of Earth. There is no reason why bisexual alien hermaphrodites could not develop along a cycle in which young females transformed into old males.

An example of this appears in the sword-tailed minnow (Xiphophorus helleri), a teleost fish that bears live young much as the mammals do. Xiphophorus females typically produce offspring until they are a few years old. Then, during a period of only a few short weeks, they take on the characteristics of the male of the species. They produce sperm and are capable of fertilizing females. Exhaustion of the ovaries is believed to trigger the changeover.

We see that both male-first and female-first alien intersexuals may be common, if not abundant, among the many intelligent extraterrestrial races in the universe.


Last updated on 6 December 2008